In the field of mobile communication systems, particularly cellular communication systems, one issue relates to radio path measurement and reporting, specifically neighbor measurement and reporting.
Conventionally, a terminal, such as a UE, performs measurements with respect to its serving base station and neighbor base stations thereof, i.e. all base station in the coverage area or cell of which the terminal resides, and reports the results to the network, i.e. a network entity such as a RNC or the like. The network can give the terminal information about what to measure, or the terminal may blindly (i.e. without any directives from the network) search and measure the neighbor base stations.
Such measurements typically relate to characteristics of the radio path (air interface) between the terminal and the respective base station, including e.g. quality and propagation measures.
The network can use the measurement reports from the terminal for decision making relating to mobility, for example in handover decisions. Also, the network can use the measurement reports to monitor and optimize transmission quality between the terminal and the respective base station. The terminal can use the measured results for similar decision making, for example in selecting the most suitable base station for an autonomous cell reselection or the like.
Such conventional measurement and reporting consumes network capacity from the radio path (air interface) for transmitting measurement reports from the terminal to the network, and increases terminal power usage for performing measurements and transmitting measurement reports. Further, the transmission of measurement reports can utilize certain signaling channels that are not always available or may be degraded in terms of transmission capacity. This may cause that the terminal has to wait until the signaling channel is available again before being able to transmit measurement reports, or that the amount of measurement results being capable of being transmitted in one measurement report, thereby resulting in latency or delay in transmission and in potential usage of the measurement results.
In case of cell change (i.e. handover), the terminal needs to obtain synchronization before the terminal can receive or transmit data. In particular, the terminal needs to obtain uplink synchronization (which can be done for example via random access procedure execution) before the terminal can transmit measurement reports to the network. However, obtaining uplink synchronization takes some time after cell change (i.e. handover), thereby resulting in latency or delay in transmission and in potential usage of the measurement results, and consumes terminal power, thereby resulting in a reduced battery lifetime of the terminal.
In view thereof, there exist problems in terms of resource and power consumption as well as latency or delay in the context of cellular radio path measurement and reporting.
Thus, there is a need to further improve cellular radio path measurement and reporting.